1 // SPDX-License-Identifier: GPL-2.0-only
3 * Scanning implementation
5 * Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi>
6 * Copyright 2004, Instant802 Networks, Inc.
7 * Copyright 2005, Devicescape Software, Inc.
8 * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz>
9 * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
10 * Copyright 2013-2015 Intel Mobile Communications GmbH
11 * Copyright 2016-2017 Intel Deutschland GmbH
12 * Copyright (C) 2018-2019 Intel Corporation
15 #include <linux/if_arp.h>
16 #include <linux/etherdevice.h>
17 #include <linux/rtnetlink.h>
18 #include <net/sch_generic.h>
19 #include <linux/slab.h>
20 #include <linux/export.h>
21 #include <linux/random.h>
22 #include <net/mac80211.h>
24 #include "ieee80211_i.h"
25 #include "driver-ops.h"
28 #define IEEE80211_PROBE_DELAY (HZ / 33)
29 #define IEEE80211_CHANNEL_TIME (HZ / 33)
30 #define IEEE80211_PASSIVE_CHANNEL_TIME (HZ / 9)
32 void ieee80211_rx_bss_put(struct ieee80211_local
*local
,
33 struct ieee80211_bss
*bss
)
37 cfg80211_put_bss(local
->hw
.wiphy
,
38 container_of((void *)bss
, struct cfg80211_bss
, priv
));
41 static bool is_uapsd_supported(struct ieee802_11_elems
*elems
)
45 if (elems
->wmm_info
&& elems
->wmm_info_len
== 7
46 && elems
->wmm_info
[5] == 1)
47 qos_info
= elems
->wmm_info
[6];
48 else if (elems
->wmm_param
&& elems
->wmm_param_len
== 24
49 && elems
->wmm_param
[5] == 1)
50 qos_info
= elems
->wmm_param
[6];
52 /* no valid wmm information or parameter element found */
55 return qos_info
& IEEE80211_WMM_IE_AP_QOSINFO_UAPSD
;
59 ieee80211_update_bss_from_elems(struct ieee80211_local
*local
,
60 struct ieee80211_bss
*bss
,
61 struct ieee802_11_elems
*elems
,
62 struct ieee80211_rx_status
*rx_status
,
68 bss
->device_ts_beacon
= rx_status
->device_timestamp
;
70 bss
->device_ts_presp
= rx_status
->device_timestamp
;
72 if (elems
->parse_error
) {
74 bss
->corrupt_data
|= IEEE80211_BSS_CORRUPT_BEACON
;
76 bss
->corrupt_data
|= IEEE80211_BSS_CORRUPT_PROBE_RESP
;
79 bss
->corrupt_data
&= ~IEEE80211_BSS_CORRUPT_BEACON
;
81 bss
->corrupt_data
&= ~IEEE80211_BSS_CORRUPT_PROBE_RESP
;
84 /* save the ERP value so that it is available at association time */
85 if (elems
->erp_info
&& (!elems
->parse_error
||
86 !(bss
->valid_data
& IEEE80211_BSS_VALID_ERP
))) {
87 bss
->erp_value
= elems
->erp_info
[0];
88 bss
->has_erp_value
= true;
89 if (!elems
->parse_error
)
90 bss
->valid_data
|= IEEE80211_BSS_VALID_ERP
;
93 /* replace old supported rates if we get new values */
94 if (!elems
->parse_error
||
95 !(bss
->valid_data
& IEEE80211_BSS_VALID_RATES
)) {
97 if (elems
->supp_rates
) {
98 clen
= IEEE80211_MAX_SUPP_RATES
;
99 if (clen
> elems
->supp_rates_len
)
100 clen
= elems
->supp_rates_len
;
101 memcpy(bss
->supp_rates
, elems
->supp_rates
, clen
);
104 if (elems
->ext_supp_rates
) {
105 clen
= IEEE80211_MAX_SUPP_RATES
- srlen
;
106 if (clen
> elems
->ext_supp_rates_len
)
107 clen
= elems
->ext_supp_rates_len
;
108 memcpy(bss
->supp_rates
+ srlen
, elems
->ext_supp_rates
,
113 bss
->supp_rates_len
= srlen
;
114 if (!elems
->parse_error
)
115 bss
->valid_data
|= IEEE80211_BSS_VALID_RATES
;
119 if (!elems
->parse_error
||
120 !(bss
->valid_data
& IEEE80211_BSS_VALID_WMM
)) {
121 bss
->wmm_used
= elems
->wmm_param
|| elems
->wmm_info
;
122 bss
->uapsd_supported
= is_uapsd_supported(elems
);
123 if (!elems
->parse_error
)
124 bss
->valid_data
|= IEEE80211_BSS_VALID_WMM
;
128 struct ieee80211_supported_band
*sband
=
129 local
->hw
.wiphy
->bands
[rx_status
->band
];
130 if (!(rx_status
->encoding
== RX_ENC_HT
) &&
131 !(rx_status
->encoding
== RX_ENC_VHT
))
133 &sband
->bitrates
[rx_status
->rate_idx
];
136 if (elems
->vht_cap_elem
)
138 le32_to_cpu(elems
->vht_cap_elem
->vht_cap_info
);
140 bss
->vht_cap_info
= 0;
143 struct ieee80211_bss
*
144 ieee80211_bss_info_update(struct ieee80211_local
*local
,
145 struct ieee80211_rx_status
*rx_status
,
146 struct ieee80211_mgmt
*mgmt
, size_t len
,
147 struct ieee80211_channel
*channel
)
149 bool beacon
= ieee80211_is_beacon(mgmt
->frame_control
);
150 struct cfg80211_bss
*cbss
, *non_tx_cbss
;
151 struct ieee80211_bss
*bss
, *non_tx_bss
;
152 struct cfg80211_inform_bss bss_meta
= {
153 .boottime_ns
= rx_status
->boottime_ns
,
156 struct ieee80211_sub_if_data
*scan_sdata
;
157 struct ieee802_11_elems elems
;
161 if (rx_status
->flag
& RX_FLAG_NO_SIGNAL_VAL
)
162 bss_meta
.signal
= 0; /* invalid signal indication */
163 else if (ieee80211_hw_check(&local
->hw
, SIGNAL_DBM
))
164 bss_meta
.signal
= rx_status
->signal
* 100;
165 else if (ieee80211_hw_check(&local
->hw
, SIGNAL_UNSPEC
))
166 bss_meta
.signal
= (rx_status
->signal
* 100) / local
->hw
.max_signal
;
168 bss_meta
.scan_width
= NL80211_BSS_CHAN_WIDTH_20
;
169 if (rx_status
->bw
== RATE_INFO_BW_5
)
170 bss_meta
.scan_width
= NL80211_BSS_CHAN_WIDTH_5
;
171 else if (rx_status
->bw
== RATE_INFO_BW_10
)
172 bss_meta
.scan_width
= NL80211_BSS_CHAN_WIDTH_10
;
174 bss_meta
.chan
= channel
;
177 scan_sdata
= rcu_dereference(local
->scan_sdata
);
178 if (scan_sdata
&& scan_sdata
->vif
.type
== NL80211_IFTYPE_STATION
&&
179 scan_sdata
->vif
.bss_conf
.assoc
&&
180 ieee80211_have_rx_timestamp(rx_status
)) {
181 bss_meta
.parent_tsf
=
182 ieee80211_calculate_rx_timestamp(local
, rx_status
,
184 ether_addr_copy(bss_meta
.parent_bssid
,
185 scan_sdata
->vif
.bss_conf
.bssid
);
189 cbss
= cfg80211_inform_bss_frame_data(local
->hw
.wiphy
, &bss_meta
,
190 mgmt
, len
, GFP_ATOMIC
);
194 if (ieee80211_is_probe_resp(mgmt
->frame_control
)) {
195 elements
= mgmt
->u
.probe_resp
.variable
;
196 baselen
= offsetof(struct ieee80211_mgmt
,
197 u
.probe_resp
.variable
);
199 baselen
= offsetof(struct ieee80211_mgmt
, u
.beacon
.variable
);
200 elements
= mgmt
->u
.beacon
.variable
;
206 ieee802_11_parse_elems(elements
, len
- baselen
, false, &elems
,
207 mgmt
->bssid
, cbss
->bssid
);
209 /* In case the signal is invalid update the status */
210 signal_valid
= channel
== cbss
->channel
;
212 rx_status
->flag
|= RX_FLAG_NO_SIGNAL_VAL
;
214 bss
= (void *)cbss
->priv
;
215 ieee80211_update_bss_from_elems(local
, bss
, &elems
, rx_status
, beacon
);
217 list_for_each_entry(non_tx_cbss
, &cbss
->nontrans_list
, nontrans_list
) {
218 non_tx_bss
= (void *)non_tx_cbss
->priv
;
220 ieee80211_update_bss_from_elems(local
, non_tx_bss
, &elems
,
227 static bool ieee80211_scan_accept_presp(struct ieee80211_sub_if_data
*sdata
,
228 u32 scan_flags
, const u8
*da
)
232 /* accept broadcast for OCE */
233 if (scan_flags
& NL80211_SCAN_FLAG_ACCEPT_BCAST_PROBE_RESP
&&
234 is_broadcast_ether_addr(da
))
236 if (scan_flags
& NL80211_SCAN_FLAG_RANDOM_ADDR
)
238 return ether_addr_equal(da
, sdata
->vif
.addr
);
241 void ieee80211_scan_rx(struct ieee80211_local
*local
, struct sk_buff
*skb
)
243 struct ieee80211_rx_status
*rx_status
= IEEE80211_SKB_RXCB(skb
);
244 struct ieee80211_sub_if_data
*sdata1
, *sdata2
;
245 struct ieee80211_mgmt
*mgmt
= (void *)skb
->data
;
246 struct ieee80211_bss
*bss
;
247 struct ieee80211_channel
*channel
;
250 (!ieee80211_is_probe_resp(mgmt
->frame_control
) &&
251 !ieee80211_is_beacon(mgmt
->frame_control
)))
254 sdata1
= rcu_dereference(local
->scan_sdata
);
255 sdata2
= rcu_dereference(local
->sched_scan_sdata
);
257 if (likely(!sdata1
&& !sdata2
))
260 if (ieee80211_is_probe_resp(mgmt
->frame_control
)) {
261 struct cfg80211_scan_request
*scan_req
;
262 struct cfg80211_sched_scan_request
*sched_scan_req
;
263 u32 scan_req_flags
= 0, sched_scan_req_flags
= 0;
265 scan_req
= rcu_dereference(local
->scan_req
);
266 sched_scan_req
= rcu_dereference(local
->sched_scan_req
);
269 scan_req_flags
= scan_req
->flags
;
272 sched_scan_req_flags
= sched_scan_req
->flags
;
274 /* ignore ProbeResp to foreign address or non-bcast (OCE)
275 * unless scanning with randomised address
277 if (!ieee80211_scan_accept_presp(sdata1
, scan_req_flags
,
279 !ieee80211_scan_accept_presp(sdata2
, sched_scan_req_flags
,
284 channel
= ieee80211_get_channel_khz(local
->hw
.wiphy
,
285 ieee80211_rx_status_to_khz(rx_status
));
287 if (!channel
|| channel
->flags
& IEEE80211_CHAN_DISABLED
)
290 bss
= ieee80211_bss_info_update(local
, rx_status
,
294 ieee80211_rx_bss_put(local
, bss
);
298 ieee80211_prepare_scan_chandef(struct cfg80211_chan_def
*chandef
,
299 enum nl80211_bss_scan_width scan_width
)
301 memset(chandef
, 0, sizeof(*chandef
));
302 switch (scan_width
) {
303 case NL80211_BSS_CHAN_WIDTH_5
:
304 chandef
->width
= NL80211_CHAN_WIDTH_5
;
306 case NL80211_BSS_CHAN_WIDTH_10
:
307 chandef
->width
= NL80211_CHAN_WIDTH_10
;
310 chandef
->width
= NL80211_CHAN_WIDTH_20_NOHT
;
315 /* return false if no more work */
316 static bool ieee80211_prep_hw_scan(struct ieee80211_sub_if_data
*sdata
)
318 struct ieee80211_local
*local
= sdata
->local
;
319 struct cfg80211_scan_request
*req
;
320 struct cfg80211_chan_def chandef
;
322 int i
, ielen
, n_chans
;
325 req
= rcu_dereference_protected(local
->scan_req
,
326 lockdep_is_held(&local
->mtx
));
328 if (test_bit(SCAN_HW_CANCELLED
, &local
->scanning
))
331 if (ieee80211_hw_check(&local
->hw
, SINGLE_SCAN_ON_ALL_BANDS
)) {
332 for (i
= 0; i
< req
->n_channels
; i
++) {
333 local
->hw_scan_req
->req
.channels
[i
] = req
->channels
[i
];
334 bands_used
|= BIT(req
->channels
[i
]->band
);
337 n_chans
= req
->n_channels
;
340 if (local
->hw_scan_band
== NUM_NL80211_BANDS
)
345 for (i
= 0; i
< req
->n_channels
; i
++) {
346 if (req
->channels
[i
]->band
!=
349 local
->hw_scan_req
->req
.channels
[n_chans
] =
352 bands_used
|= BIT(req
->channels
[i
]->band
);
355 local
->hw_scan_band
++;
359 local
->hw_scan_req
->req
.n_channels
= n_chans
;
360 ieee80211_prepare_scan_chandef(&chandef
, req
->scan_width
);
362 if (req
->flags
& NL80211_SCAN_FLAG_MIN_PREQ_CONTENT
)
363 flags
|= IEEE80211_PROBE_FLAG_MIN_CONTENT
;
365 ielen
= ieee80211_build_preq_ies(sdata
,
366 (u8
*)local
->hw_scan_req
->req
.ie
,
367 local
->hw_scan_ies_bufsize
,
368 &local
->hw_scan_req
->ies
,
369 req
->ie
, req
->ie_len
,
370 bands_used
, req
->rates
, &chandef
,
372 local
->hw_scan_req
->req
.ie_len
= ielen
;
373 local
->hw_scan_req
->req
.no_cck
= req
->no_cck
;
374 ether_addr_copy(local
->hw_scan_req
->req
.mac_addr
, req
->mac_addr
);
375 ether_addr_copy(local
->hw_scan_req
->req
.mac_addr_mask
,
377 ether_addr_copy(local
->hw_scan_req
->req
.bssid
, req
->bssid
);
382 static void __ieee80211_scan_completed(struct ieee80211_hw
*hw
, bool aborted
)
384 struct ieee80211_local
*local
= hw_to_local(hw
);
385 bool hw_scan
= test_bit(SCAN_HW_SCANNING
, &local
->scanning
);
386 bool was_scanning
= local
->scanning
;
387 struct cfg80211_scan_request
*scan_req
;
388 struct ieee80211_sub_if_data
*scan_sdata
;
389 struct ieee80211_sub_if_data
*sdata
;
391 lockdep_assert_held(&local
->mtx
);
394 * It's ok to abort a not-yet-running scan (that
395 * we have one at all will be verified by checking
396 * local->scan_req next), but not to complete it
399 if (WARN_ON(!local
->scanning
&& !aborted
))
402 if (WARN_ON(!local
->scan_req
))
405 scan_sdata
= rcu_dereference_protected(local
->scan_sdata
,
406 lockdep_is_held(&local
->mtx
));
408 if (hw_scan
&& !aborted
&&
409 !ieee80211_hw_check(&local
->hw
, SINGLE_SCAN_ON_ALL_BANDS
) &&
410 ieee80211_prep_hw_scan(scan_sdata
)) {
413 rc
= drv_hw_scan(local
,
414 rcu_dereference_protected(local
->scan_sdata
,
415 lockdep_is_held(&local
->mtx
)),
421 /* HW scan failed and is going to be reported as aborted,
422 * so clear old scan info.
424 memset(&local
->scan_info
, 0, sizeof(local
->scan_info
));
428 kfree(local
->hw_scan_req
);
429 local
->hw_scan_req
= NULL
;
431 scan_req
= rcu_dereference_protected(local
->scan_req
,
432 lockdep_is_held(&local
->mtx
));
434 if (scan_req
!= local
->int_scan_req
) {
435 local
->scan_info
.aborted
= aborted
;
436 cfg80211_scan_done(scan_req
, &local
->scan_info
);
438 RCU_INIT_POINTER(local
->scan_req
, NULL
);
439 RCU_INIT_POINTER(local
->scan_sdata
, NULL
);
442 local
->scan_chandef
.chan
= NULL
;
444 /* Set power back to normal operating levels. */
445 ieee80211_hw_config(local
, 0);
448 ieee80211_configure_filter(local
);
449 drv_sw_scan_complete(local
, scan_sdata
);
450 ieee80211_offchannel_return(local
);
453 ieee80211_recalc_idle(local
);
455 ieee80211_mlme_notify_scan_completed(local
);
456 ieee80211_ibss_notify_scan_completed(local
);
458 /* Requeue all the work that might have been ignored while
459 * the scan was in progress; if there was none this will
460 * just be a no-op for the particular interface.
462 list_for_each_entry_rcu(sdata
, &local
->interfaces
, list
) {
463 if (ieee80211_sdata_running(sdata
))
464 ieee80211_queue_work(&sdata
->local
->hw
, &sdata
->work
);
468 ieee80211_start_next_roc(local
);
471 void ieee80211_scan_completed(struct ieee80211_hw
*hw
,
472 struct cfg80211_scan_info
*info
)
474 struct ieee80211_local
*local
= hw_to_local(hw
);
476 trace_api_scan_completed(local
, info
->aborted
);
478 set_bit(SCAN_COMPLETED
, &local
->scanning
);
480 set_bit(SCAN_ABORTED
, &local
->scanning
);
482 memcpy(&local
->scan_info
, info
, sizeof(*info
));
484 ieee80211_queue_delayed_work(&local
->hw
, &local
->scan_work
, 0);
486 EXPORT_SYMBOL(ieee80211_scan_completed
);
488 static int ieee80211_start_sw_scan(struct ieee80211_local
*local
,
489 struct ieee80211_sub_if_data
*sdata
)
491 /* Software scan is not supported in multi-channel cases */
492 if (local
->use_chanctx
)
496 * Hardware/driver doesn't support hw_scan, so use software
497 * scanning instead. First send a nullfunc frame with power save
498 * bit on so that AP will buffer the frames for us while we are not
499 * listening, then send probe requests to each channel and wait for
500 * the responses. After all channels are scanned, tune back to the
501 * original channel and send a nullfunc frame with power save bit
502 * off to trigger the AP to send us all the buffered frames.
504 * Note that while local->sw_scanning is true everything else but
505 * nullfunc frames and probe requests will be dropped in
506 * ieee80211_tx_h_check_assoc().
508 drv_sw_scan_start(local
, sdata
, local
->scan_addr
);
510 local
->leave_oper_channel_time
= jiffies
;
511 local
->next_scan_state
= SCAN_DECISION
;
512 local
->scan_channel_idx
= 0;
514 ieee80211_offchannel_stop_vifs(local
);
516 /* ensure nullfunc is transmitted before leaving operating channel */
517 ieee80211_flush_queues(local
, NULL
, false);
519 ieee80211_configure_filter(local
);
521 /* We need to set power level at maximum rate for scanning. */
522 ieee80211_hw_config(local
, 0);
524 ieee80211_queue_delayed_work(&local
->hw
,
525 &local
->scan_work
, 0);
530 static bool __ieee80211_can_leave_ch(struct ieee80211_sub_if_data
*sdata
)
532 struct ieee80211_local
*local
= sdata
->local
;
533 struct ieee80211_sub_if_data
*sdata_iter
;
535 if (!ieee80211_is_radar_required(local
))
538 if (!regulatory_pre_cac_allowed(local
->hw
.wiphy
))
541 mutex_lock(&local
->iflist_mtx
);
542 list_for_each_entry(sdata_iter
, &local
->interfaces
, list
) {
543 if (sdata_iter
->wdev
.cac_started
) {
544 mutex_unlock(&local
->iflist_mtx
);
548 mutex_unlock(&local
->iflist_mtx
);
553 static bool ieee80211_can_scan(struct ieee80211_local
*local
,
554 struct ieee80211_sub_if_data
*sdata
)
556 if (!__ieee80211_can_leave_ch(sdata
))
559 if (!list_empty(&local
->roc_list
))
562 if (sdata
->vif
.type
== NL80211_IFTYPE_STATION
&&
563 sdata
->u
.mgd
.flags
& IEEE80211_STA_CONNECTION_POLL
)
569 void ieee80211_run_deferred_scan(struct ieee80211_local
*local
)
571 lockdep_assert_held(&local
->mtx
);
573 if (!local
->scan_req
|| local
->scanning
)
576 if (!ieee80211_can_scan(local
,
577 rcu_dereference_protected(
579 lockdep_is_held(&local
->mtx
))))
582 ieee80211_queue_delayed_work(&local
->hw
, &local
->scan_work
,
583 round_jiffies_relative(0));
586 static void ieee80211_send_scan_probe_req(struct ieee80211_sub_if_data
*sdata
,
587 const u8
*src
, const u8
*dst
,
588 const u8
*ssid
, size_t ssid_len
,
589 const u8
*ie
, size_t ie_len
,
590 u32 ratemask
, u32 flags
, u32 tx_flags
,
591 struct ieee80211_channel
*channel
)
595 skb
= ieee80211_build_probe_req(sdata
, src
, dst
, ratemask
, channel
,
600 if (flags
& IEEE80211_PROBE_FLAG_RANDOM_SN
) {
601 struct ieee80211_hdr
*hdr
= (void *)skb
->data
;
602 struct ieee80211_tx_info
*info
= IEEE80211_SKB_CB(skb
);
603 u16 sn
= get_random_u32();
605 info
->control
.flags
|= IEEE80211_TX_CTRL_NO_SEQNO
;
607 cpu_to_le16(IEEE80211_SN_TO_SEQ(sn
));
609 IEEE80211_SKB_CB(skb
)->flags
|= tx_flags
;
610 ieee80211_tx_skb_tid_band(sdata
, skb
, 7, channel
->band
);
614 static void ieee80211_scan_state_send_probe(struct ieee80211_local
*local
,
615 unsigned long *next_delay
)
618 struct ieee80211_sub_if_data
*sdata
;
619 struct cfg80211_scan_request
*scan_req
;
620 enum nl80211_band band
= local
->hw
.conf
.chandef
.chan
->band
;
621 u32 flags
= 0, tx_flags
;
623 scan_req
= rcu_dereference_protected(local
->scan_req
,
624 lockdep_is_held(&local
->mtx
));
626 tx_flags
= IEEE80211_TX_INTFL_OFFCHAN_TX_OK
;
627 if (scan_req
->no_cck
)
628 tx_flags
|= IEEE80211_TX_CTL_NO_CCK_RATE
;
629 if (scan_req
->flags
& NL80211_SCAN_FLAG_MIN_PREQ_CONTENT
)
630 flags
|= IEEE80211_PROBE_FLAG_MIN_CONTENT
;
631 if (scan_req
->flags
& NL80211_SCAN_FLAG_RANDOM_SN
)
632 flags
|= IEEE80211_PROBE_FLAG_RANDOM_SN
;
634 sdata
= rcu_dereference_protected(local
->scan_sdata
,
635 lockdep_is_held(&local
->mtx
));
637 for (i
= 0; i
< scan_req
->n_ssids
; i
++)
638 ieee80211_send_scan_probe_req(
639 sdata
, local
->scan_addr
, scan_req
->bssid
,
640 scan_req
->ssids
[i
].ssid
, scan_req
->ssids
[i
].ssid_len
,
641 scan_req
->ie
, scan_req
->ie_len
,
642 scan_req
->rates
[band
], flags
,
643 tx_flags
, local
->hw
.conf
.chandef
.chan
);
646 * After sending probe requests, wait for probe responses
649 *next_delay
= IEEE80211_CHANNEL_TIME
;
650 local
->next_scan_state
= SCAN_DECISION
;
653 static int __ieee80211_start_scan(struct ieee80211_sub_if_data
*sdata
,
654 struct cfg80211_scan_request
*req
)
656 struct ieee80211_local
*local
= sdata
->local
;
657 bool hw_scan
= local
->ops
->hw_scan
;
660 lockdep_assert_held(&local
->mtx
);
665 if (!__ieee80211_can_leave_ch(sdata
))
668 if (!ieee80211_can_scan(local
, sdata
)) {
669 /* wait for the work to finish/time out */
670 rcu_assign_pointer(local
->scan_req
, req
);
671 rcu_assign_pointer(local
->scan_sdata
, sdata
);
679 local
->hw_scan_ies_bufsize
= local
->scan_ies_len
+ req
->ie_len
;
681 if (ieee80211_hw_check(&local
->hw
, SINGLE_SCAN_ON_ALL_BANDS
)) {
683 u8 bands_counted
= 0;
685 for (i
= 0; i
< req
->n_channels
; i
++) {
686 if (bands_counted
& BIT(req
->channels
[i
]->band
))
688 bands_counted
|= BIT(req
->channels
[i
]->band
);
692 local
->hw_scan_ies_bufsize
*= n_bands
;
695 local
->hw_scan_req
= kmalloc(
696 sizeof(*local
->hw_scan_req
) +
697 req
->n_channels
* sizeof(req
->channels
[0]) +
698 local
->hw_scan_ies_bufsize
, GFP_KERNEL
);
699 if (!local
->hw_scan_req
)
702 local
->hw_scan_req
->req
.ssids
= req
->ssids
;
703 local
->hw_scan_req
->req
.n_ssids
= req
->n_ssids
;
704 ies
= (u8
*)local
->hw_scan_req
+
705 sizeof(*local
->hw_scan_req
) +
706 req
->n_channels
* sizeof(req
->channels
[0]);
707 local
->hw_scan_req
->req
.ie
= ies
;
708 local
->hw_scan_req
->req
.flags
= req
->flags
;
709 eth_broadcast_addr(local
->hw_scan_req
->req
.bssid
);
710 local
->hw_scan_req
->req
.duration
= req
->duration
;
711 local
->hw_scan_req
->req
.duration_mandatory
=
712 req
->duration_mandatory
;
714 local
->hw_scan_band
= 0;
717 * After allocating local->hw_scan_req, we must
718 * go through until ieee80211_prep_hw_scan(), so
719 * anything that might be changed here and leave
720 * this function early must not go after this
725 rcu_assign_pointer(local
->scan_req
, req
);
726 rcu_assign_pointer(local
->scan_sdata
, sdata
);
728 if (req
->flags
& NL80211_SCAN_FLAG_RANDOM_ADDR
)
729 get_random_mask_addr(local
->scan_addr
,
733 memcpy(local
->scan_addr
, sdata
->vif
.addr
, ETH_ALEN
);
736 __set_bit(SCAN_HW_SCANNING
, &local
->scanning
);
737 } else if ((req
->n_channels
== 1) &&
738 (req
->channels
[0] == local
->_oper_chandef
.chan
)) {
740 * If we are scanning only on the operating channel
741 * then we do not need to stop normal activities
743 unsigned long next_delay
;
745 __set_bit(SCAN_ONCHANNEL_SCANNING
, &local
->scanning
);
747 ieee80211_recalc_idle(local
);
749 /* Notify driver scan is starting, keep order of operations
750 * same as normal software scan, in case that matters. */
751 drv_sw_scan_start(local
, sdata
, local
->scan_addr
);
753 ieee80211_configure_filter(local
); /* accept probe-responses */
755 /* We need to ensure power level is at max for scanning. */
756 ieee80211_hw_config(local
, 0);
758 if ((req
->channels
[0]->flags
& (IEEE80211_CHAN_NO_IR
|
759 IEEE80211_CHAN_RADAR
)) ||
761 next_delay
= IEEE80211_PASSIVE_CHANNEL_TIME
;
763 ieee80211_scan_state_send_probe(local
, &next_delay
);
764 next_delay
= IEEE80211_CHANNEL_TIME
;
767 /* Now, just wait a bit and we are all done! */
768 ieee80211_queue_delayed_work(&local
->hw
, &local
->scan_work
,
772 /* Do normal software scan */
773 __set_bit(SCAN_SW_SCANNING
, &local
->scanning
);
776 ieee80211_recalc_idle(local
);
779 WARN_ON(!ieee80211_prep_hw_scan(sdata
));
780 rc
= drv_hw_scan(local
, sdata
, local
->hw_scan_req
);
782 rc
= ieee80211_start_sw_scan(local
, sdata
);
786 kfree(local
->hw_scan_req
);
787 local
->hw_scan_req
= NULL
;
790 ieee80211_recalc_idle(local
);
792 local
->scan_req
= NULL
;
793 RCU_INIT_POINTER(local
->scan_sdata
, NULL
);
796 if (hw_scan
&& rc
== 1) {
798 * we can't fall back to software for P2P-GO
799 * as it must update NoA etc.
801 if (ieee80211_vif_type_p2p(&sdata
->vif
) ==
802 NL80211_IFTYPE_P2P_GO
)
812 ieee80211_scan_get_channel_time(struct ieee80211_channel
*chan
)
815 * TODO: channel switching also consumes quite some time,
816 * add that delay as well to get a better estimation
818 if (chan
->flags
& (IEEE80211_CHAN_NO_IR
| IEEE80211_CHAN_RADAR
))
819 return IEEE80211_PASSIVE_CHANNEL_TIME
;
820 return IEEE80211_PROBE_DELAY
+ IEEE80211_CHANNEL_TIME
;
823 static void ieee80211_scan_state_decision(struct ieee80211_local
*local
,
824 unsigned long *next_delay
)
826 bool associated
= false;
827 bool tx_empty
= true;
829 struct ieee80211_sub_if_data
*sdata
;
830 struct ieee80211_channel
*next_chan
;
831 enum mac80211_scan_state next_scan_state
;
832 struct cfg80211_scan_request
*scan_req
;
835 * check if at least one STA interface is associated,
836 * check if at least one STA interface has pending tx frames
837 * and grab the lowest used beacon interval
839 mutex_lock(&local
->iflist_mtx
);
840 list_for_each_entry(sdata
, &local
->interfaces
, list
) {
841 if (!ieee80211_sdata_running(sdata
))
844 if (sdata
->vif
.type
== NL80211_IFTYPE_STATION
) {
845 if (sdata
->u
.mgd
.associated
) {
848 if (!qdisc_all_tx_empty(sdata
->dev
)) {
855 mutex_unlock(&local
->iflist_mtx
);
857 scan_req
= rcu_dereference_protected(local
->scan_req
,
858 lockdep_is_held(&local
->mtx
));
860 next_chan
= scan_req
->channels
[local
->scan_channel_idx
];
863 * we're currently scanning a different channel, let's
864 * see if we can scan another channel without interfering
865 * with the current traffic situation.
867 * Keep good latency, do not stay off-channel more than 125 ms.
870 bad_latency
= time_after(jiffies
+
871 ieee80211_scan_get_channel_time(next_chan
),
872 local
->leave_oper_channel_time
+ HZ
/ 8);
874 if (associated
&& !tx_empty
) {
875 if (scan_req
->flags
& NL80211_SCAN_FLAG_LOW_PRIORITY
)
876 next_scan_state
= SCAN_ABORT
;
878 next_scan_state
= SCAN_SUSPEND
;
879 } else if (associated
&& bad_latency
) {
880 next_scan_state
= SCAN_SUSPEND
;
882 next_scan_state
= SCAN_SET_CHANNEL
;
885 local
->next_scan_state
= next_scan_state
;
890 static void ieee80211_scan_state_set_channel(struct ieee80211_local
*local
,
891 unsigned long *next_delay
)
894 struct ieee80211_channel
*chan
;
895 enum nl80211_bss_scan_width oper_scan_width
;
896 struct cfg80211_scan_request
*scan_req
;
898 scan_req
= rcu_dereference_protected(local
->scan_req
,
899 lockdep_is_held(&local
->mtx
));
902 chan
= scan_req
->channels
[local
->scan_channel_idx
];
904 local
->scan_chandef
.chan
= chan
;
905 local
->scan_chandef
.center_freq1
= chan
->center_freq
;
906 local
->scan_chandef
.freq1_offset
= chan
->freq_offset
;
907 local
->scan_chandef
.center_freq2
= 0;
908 switch (scan_req
->scan_width
) {
909 case NL80211_BSS_CHAN_WIDTH_5
:
910 local
->scan_chandef
.width
= NL80211_CHAN_WIDTH_5
;
912 case NL80211_BSS_CHAN_WIDTH_10
:
913 local
->scan_chandef
.width
= NL80211_CHAN_WIDTH_10
;
916 case NL80211_BSS_CHAN_WIDTH_20
:
917 /* If scanning on oper channel, use whatever channel-type
918 * is currently in use.
920 oper_scan_width
= cfg80211_chandef_to_scan_width(
921 &local
->_oper_chandef
);
922 if (chan
== local
->_oper_chandef
.chan
&&
923 oper_scan_width
== scan_req
->scan_width
)
924 local
->scan_chandef
= local
->_oper_chandef
;
926 local
->scan_chandef
.width
= NL80211_CHAN_WIDTH_20_NOHT
;
930 if (ieee80211_hw_config(local
, IEEE80211_CONF_CHANGE_CHANNEL
))
933 /* advance state machine to next channel/band */
934 local
->scan_channel_idx
++;
937 /* if we skip this channel return to the decision state */
938 local
->next_scan_state
= SCAN_DECISION
;
943 * Probe delay is used to update the NAV, cf. 11.1.3.2.2
944 * (which unfortunately doesn't say _why_ step a) is done,
945 * but it waits for the probe delay or until a frame is
946 * received - and the received frame would update the NAV).
947 * For now, we do not support waiting until a frame is
950 * In any case, it is not necessary for a passive scan.
952 if ((chan
->flags
& (IEEE80211_CHAN_NO_IR
| IEEE80211_CHAN_RADAR
)) ||
953 !scan_req
->n_ssids
) {
954 *next_delay
= IEEE80211_PASSIVE_CHANNEL_TIME
;
955 local
->next_scan_state
= SCAN_DECISION
;
959 /* active scan, send probes */
960 *next_delay
= IEEE80211_PROBE_DELAY
;
961 local
->next_scan_state
= SCAN_SEND_PROBE
;
964 static void ieee80211_scan_state_suspend(struct ieee80211_local
*local
,
965 unsigned long *next_delay
)
967 /* switch back to the operating channel */
968 local
->scan_chandef
.chan
= NULL
;
969 ieee80211_hw_config(local
, IEEE80211_CONF_CHANGE_CHANNEL
);
972 ieee80211_offchannel_return(local
);
974 *next_delay
= HZ
/ 5;
975 /* afterwards, resume scan & go to next channel */
976 local
->next_scan_state
= SCAN_RESUME
;
979 static void ieee80211_scan_state_resume(struct ieee80211_local
*local
,
980 unsigned long *next_delay
)
982 ieee80211_offchannel_stop_vifs(local
);
984 if (local
->ops
->flush
) {
985 ieee80211_flush_queues(local
, NULL
, false);
988 *next_delay
= HZ
/ 10;
990 /* remember when we left the operating channel */
991 local
->leave_oper_channel_time
= jiffies
;
993 /* advance to the next channel to be scanned */
994 local
->next_scan_state
= SCAN_SET_CHANNEL
;
997 void ieee80211_scan_work(struct work_struct
*work
)
999 struct ieee80211_local
*local
=
1000 container_of(work
, struct ieee80211_local
, scan_work
.work
);
1001 struct ieee80211_sub_if_data
*sdata
;
1002 struct cfg80211_scan_request
*scan_req
;
1003 unsigned long next_delay
= 0;
1006 mutex_lock(&local
->mtx
);
1008 if (!ieee80211_can_run_worker(local
)) {
1013 sdata
= rcu_dereference_protected(local
->scan_sdata
,
1014 lockdep_is_held(&local
->mtx
));
1015 scan_req
= rcu_dereference_protected(local
->scan_req
,
1016 lockdep_is_held(&local
->mtx
));
1018 /* When scanning on-channel, the first-callback means completed. */
1019 if (test_bit(SCAN_ONCHANNEL_SCANNING
, &local
->scanning
)) {
1020 aborted
= test_and_clear_bit(SCAN_ABORTED
, &local
->scanning
);
1024 if (test_and_clear_bit(SCAN_COMPLETED
, &local
->scanning
)) {
1025 aborted
= test_and_clear_bit(SCAN_ABORTED
, &local
->scanning
);
1029 if (!sdata
|| !scan_req
)
1032 if (!local
->scanning
) {
1035 RCU_INIT_POINTER(local
->scan_req
, NULL
);
1036 RCU_INIT_POINTER(local
->scan_sdata
, NULL
);
1038 rc
= __ieee80211_start_scan(sdata
, scan_req
);
1040 /* need to complete scan in cfg80211 */
1041 rcu_assign_pointer(local
->scan_req
, scan_req
);
1049 * as long as no delay is required advance immediately
1050 * without scheduling a new work
1053 if (!ieee80211_sdata_running(sdata
)) {
1058 switch (local
->next_scan_state
) {
1060 /* if no more bands/channels left, complete scan */
1061 if (local
->scan_channel_idx
>= scan_req
->n_channels
) {
1065 ieee80211_scan_state_decision(local
, &next_delay
);
1067 case SCAN_SET_CHANNEL
:
1068 ieee80211_scan_state_set_channel(local
, &next_delay
);
1070 case SCAN_SEND_PROBE
:
1071 ieee80211_scan_state_send_probe(local
, &next_delay
);
1074 ieee80211_scan_state_suspend(local
, &next_delay
);
1077 ieee80211_scan_state_resume(local
, &next_delay
);
1083 } while (next_delay
== 0);
1085 ieee80211_queue_delayed_work(&local
->hw
, &local
->scan_work
, next_delay
);
1089 __ieee80211_scan_completed(&local
->hw
, aborted
);
1091 mutex_unlock(&local
->mtx
);
1094 int ieee80211_request_scan(struct ieee80211_sub_if_data
*sdata
,
1095 struct cfg80211_scan_request
*req
)
1099 mutex_lock(&sdata
->local
->mtx
);
1100 res
= __ieee80211_start_scan(sdata
, req
);
1101 mutex_unlock(&sdata
->local
->mtx
);
1106 int ieee80211_request_ibss_scan(struct ieee80211_sub_if_data
*sdata
,
1107 const u8
*ssid
, u8 ssid_len
,
1108 struct ieee80211_channel
**channels
,
1109 unsigned int n_channels
,
1110 enum nl80211_bss_scan_width scan_width
)
1112 struct ieee80211_local
*local
= sdata
->local
;
1113 int ret
= -EBUSY
, i
, n_ch
= 0;
1114 enum nl80211_band band
;
1116 mutex_lock(&local
->mtx
);
1119 if (local
->scan_req
)
1122 /* fill internal scan request */
1126 for (band
= 0; band
< NUM_NL80211_BANDS
; band
++) {
1127 if (!local
->hw
.wiphy
->bands
[band
])
1130 max_n
= local
->hw
.wiphy
->bands
[band
]->n_channels
;
1131 for (i
= 0; i
< max_n
; i
++) {
1132 struct ieee80211_channel
*tmp_ch
=
1133 &local
->hw
.wiphy
->bands
[band
]->channels
[i
];
1135 if (tmp_ch
->flags
& (IEEE80211_CHAN_NO_IR
|
1136 IEEE80211_CHAN_DISABLED
))
1139 local
->int_scan_req
->channels
[n_ch
] = tmp_ch
;
1144 if (WARN_ON_ONCE(n_ch
== 0))
1147 local
->int_scan_req
->n_channels
= n_ch
;
1149 for (i
= 0; i
< n_channels
; i
++) {
1150 if (channels
[i
]->flags
& (IEEE80211_CHAN_NO_IR
|
1151 IEEE80211_CHAN_DISABLED
))
1154 local
->int_scan_req
->channels
[n_ch
] = channels
[i
];
1158 if (WARN_ON_ONCE(n_ch
== 0))
1161 local
->int_scan_req
->n_channels
= n_ch
;
1164 local
->int_scan_req
->ssids
= &local
->scan_ssid
;
1165 local
->int_scan_req
->n_ssids
= 1;
1166 local
->int_scan_req
->scan_width
= scan_width
;
1167 memcpy(local
->int_scan_req
->ssids
[0].ssid
, ssid
, IEEE80211_MAX_SSID_LEN
);
1168 local
->int_scan_req
->ssids
[0].ssid_len
= ssid_len
;
1170 ret
= __ieee80211_start_scan(sdata
, sdata
->local
->int_scan_req
);
1172 mutex_unlock(&local
->mtx
);
1177 * Only call this function when a scan can't be queued -- under RTNL.
1179 void ieee80211_scan_cancel(struct ieee80211_local
*local
)
1182 * We are canceling software scan, or deferred scan that was not
1183 * yet really started (see __ieee80211_start_scan ).
1185 * Regarding hardware scan:
1186 * - we can not call __ieee80211_scan_completed() as when
1187 * SCAN_HW_SCANNING bit is set this function change
1188 * local->hw_scan_req to operate on 5G band, what race with
1189 * driver which can use local->hw_scan_req
1191 * - we can not cancel scan_work since driver can schedule it
1192 * by ieee80211_scan_completed(..., true) to finish scan
1194 * Hence we only call the cancel_hw_scan() callback, but the low-level
1195 * driver is still responsible for calling ieee80211_scan_completed()
1196 * after the scan was completed/aborted.
1199 mutex_lock(&local
->mtx
);
1200 if (!local
->scan_req
)
1204 * We have a scan running and the driver already reported completion,
1205 * but the worker hasn't run yet or is stuck on the mutex - mark it as
1208 if (test_bit(SCAN_HW_SCANNING
, &local
->scanning
) &&
1209 test_bit(SCAN_COMPLETED
, &local
->scanning
)) {
1210 set_bit(SCAN_HW_CANCELLED
, &local
->scanning
);
1214 if (test_bit(SCAN_HW_SCANNING
, &local
->scanning
)) {
1216 * Make sure that __ieee80211_scan_completed doesn't trigger a
1217 * scan on another band.
1219 set_bit(SCAN_HW_CANCELLED
, &local
->scanning
);
1220 if (local
->ops
->cancel_hw_scan
)
1221 drv_cancel_hw_scan(local
,
1222 rcu_dereference_protected(local
->scan_sdata
,
1223 lockdep_is_held(&local
->mtx
)));
1228 * If the work is currently running, it must be blocked on
1229 * the mutex, but we'll set scan_sdata = NULL and it'll
1230 * simply exit once it acquires the mutex.
1232 cancel_delayed_work(&local
->scan_work
);
1234 memset(&local
->scan_info
, 0, sizeof(local
->scan_info
));
1235 __ieee80211_scan_completed(&local
->hw
, true);
1237 mutex_unlock(&local
->mtx
);
1240 int __ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data
*sdata
,
1241 struct cfg80211_sched_scan_request
*req
)
1243 struct ieee80211_local
*local
= sdata
->local
;
1244 struct ieee80211_scan_ies sched_scan_ies
= {};
1245 struct cfg80211_chan_def chandef
;
1246 int ret
, i
, iebufsz
, num_bands
= 0;
1247 u32 rate_masks
[NUM_NL80211_BANDS
] = {};
1252 iebufsz
= local
->scan_ies_len
+ req
->ie_len
;
1254 lockdep_assert_held(&local
->mtx
);
1256 if (!local
->ops
->sched_scan_start
)
1259 for (i
= 0; i
< NUM_NL80211_BANDS
; i
++) {
1260 if (local
->hw
.wiphy
->bands
[i
]) {
1261 bands_used
|= BIT(i
);
1262 rate_masks
[i
] = (u32
) -1;
1267 if (req
->flags
& NL80211_SCAN_FLAG_MIN_PREQ_CONTENT
)
1268 flags
|= IEEE80211_PROBE_FLAG_MIN_CONTENT
;
1270 ie
= kcalloc(iebufsz
, num_bands
, GFP_KERNEL
);
1276 ieee80211_prepare_scan_chandef(&chandef
, req
->scan_width
);
1278 ieee80211_build_preq_ies(sdata
, ie
, num_bands
* iebufsz
,
1279 &sched_scan_ies
, req
->ie
,
1280 req
->ie_len
, bands_used
, rate_masks
, &chandef
,
1283 ret
= drv_sched_scan_start(local
, sdata
, req
, &sched_scan_ies
);
1285 rcu_assign_pointer(local
->sched_scan_sdata
, sdata
);
1286 rcu_assign_pointer(local
->sched_scan_req
, req
);
1293 /* Clean in case of failure after HW restart or upon resume. */
1294 RCU_INIT_POINTER(local
->sched_scan_sdata
, NULL
);
1295 RCU_INIT_POINTER(local
->sched_scan_req
, NULL
);
1301 int ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data
*sdata
,
1302 struct cfg80211_sched_scan_request
*req
)
1304 struct ieee80211_local
*local
= sdata
->local
;
1307 mutex_lock(&local
->mtx
);
1309 if (rcu_access_pointer(local
->sched_scan_sdata
)) {
1310 mutex_unlock(&local
->mtx
);
1314 ret
= __ieee80211_request_sched_scan_start(sdata
, req
);
1316 mutex_unlock(&local
->mtx
);
1320 int ieee80211_request_sched_scan_stop(struct ieee80211_local
*local
)
1322 struct ieee80211_sub_if_data
*sched_scan_sdata
;
1325 mutex_lock(&local
->mtx
);
1327 if (!local
->ops
->sched_scan_stop
) {
1332 /* We don't want to restart sched scan anymore. */
1333 RCU_INIT_POINTER(local
->sched_scan_req
, NULL
);
1335 sched_scan_sdata
= rcu_dereference_protected(local
->sched_scan_sdata
,
1336 lockdep_is_held(&local
->mtx
));
1337 if (sched_scan_sdata
) {
1338 ret
= drv_sched_scan_stop(local
, sched_scan_sdata
);
1340 RCU_INIT_POINTER(local
->sched_scan_sdata
, NULL
);
1343 mutex_unlock(&local
->mtx
);
1348 void ieee80211_sched_scan_results(struct ieee80211_hw
*hw
)
1350 struct ieee80211_local
*local
= hw_to_local(hw
);
1352 trace_api_sched_scan_results(local
);
1354 cfg80211_sched_scan_results(hw
->wiphy
, 0);
1356 EXPORT_SYMBOL(ieee80211_sched_scan_results
);
1358 void ieee80211_sched_scan_end(struct ieee80211_local
*local
)
1360 mutex_lock(&local
->mtx
);
1362 if (!rcu_access_pointer(local
->sched_scan_sdata
)) {
1363 mutex_unlock(&local
->mtx
);
1367 RCU_INIT_POINTER(local
->sched_scan_sdata
, NULL
);
1369 /* If sched scan was aborted by the driver. */
1370 RCU_INIT_POINTER(local
->sched_scan_req
, NULL
);
1372 mutex_unlock(&local
->mtx
);
1374 cfg80211_sched_scan_stopped(local
->hw
.wiphy
, 0);
1377 void ieee80211_sched_scan_stopped_work(struct work_struct
*work
)
1379 struct ieee80211_local
*local
=
1380 container_of(work
, struct ieee80211_local
,
1381 sched_scan_stopped_work
);
1383 ieee80211_sched_scan_end(local
);
1386 void ieee80211_sched_scan_stopped(struct ieee80211_hw
*hw
)
1388 struct ieee80211_local
*local
= hw_to_local(hw
);
1390 trace_api_sched_scan_stopped(local
);
1393 * this shouldn't really happen, so for simplicity
1394 * simply ignore it, and let mac80211 reconfigure
1395 * the sched scan later on.
1397 if (local
->in_reconfig
)
1400 schedule_work(&local
->sched_scan_stopped_work
);
1402 EXPORT_SYMBOL(ieee80211_sched_scan_stopped
);